1. Field of the Invention
The present invention relates to an object, a method, or a manufacturing method. The present invention relates to a process, a machine, manufacture, or a composition of matter. One embodiment of the present invention relates to a semiconductor device, a display device, a light-emitting device, a power storage device, a driving method therefor, or a manufacturing method therefor. In particular, one embodiment of the present invention relates to a fabricating apparatus for a secondary battery.
Note that electronic devices in this specification mean all devices including secondary batteries, and electro-optical devices including secondary batteries, information terminal devices including secondary batteries, vehicles including secondary batteries, and the like are all electronic devices.
2. Description of the Related Art
In recent years, portable information terminals typified by smartphones have been actively developed. Portable information terminals, which are a kind of electronic devices, are desired to be lightweight and compact by users.
Patent Document 1 discloses an example of a hands-free wearable device with which information can be visually obtained anywhere, specifically, a google-type display device that includes a CPU and is capable of data communication. The device disclosed in Patent Document 1 is also a kind of electronic device.
Most wearable devices and portable information terminals include secondary batteries (also referred to as batteries) that can be repeatedly charged and discharged, and have problems in that there is a limitation on the time for operation of the wearable devices and the portable information terminals because their light weight and compactness limit the battery capacity. Secondary batteries used in wearable devices and portable information terminals should be lightweight and should be able to be used for a long time.
Examples of secondary batteries include a nickel-metal hydride battery and a lithium-ion secondary battery. In particular, lithium-ion secondary batteries have been actively researched and developed because the capacity thereof can be increased and the size thereof can be reduced.
Electrodes serving as positive electrodes or negative electrodes of lithium-ion secondary batteries are each formed using, for example, metal lithium, a carbon-based material, or an alloy-based material. Lithium-ion secondary batteries are divided into lithium metal batteries, lithium-ion secondary batteries, and lithium polymer secondary batteries according to the kind of electrolyte. Furthermore, batteries are divided into thin (laminated) batteries, cylindrical batteries, coin-type batteries, and rectangular batteries according to the kind of an exterior material in which electrodes and an electrolyte are packed.
Patent Document 2 discloses a fabricating method for a lithium-ion secondary battery that improves cycle performance by using an alloy-based material (e.g., silicon) with increased reactivity with lithium for a negative electrode active material.